I have a lot of student debt including overdrafts and credit cards, although I have been making payments since I graduated. I have checked with Experian and Equifax and my credit score and credit rating are both excellent because I haven't missed any payments and manage my debt well. That does not mean that I will be accepted for credit with HSBC, which is a source of worry for me too. I have no problem getting credit elsewhere (to move my debts, not increase them) but then I've never applied to borrow £60,000 unsecured before. I know that I can manage my debts while training, but that may not be enough for HSBC.
I have a feeling that if you have not made any payments to your credit card at all you will have serious problems getting credit. However, the agreement between CTC and HSBC is in a league of its own so I think that only someone who has experienced this situation, or someone from CTC itself, could answer this question properly.
As for the student loan, the companies that provide them will only take money from you if you are earning a certain salary. If you are training with CTC you won't be on a salary and therefore shouldn't be required to make payments. As such, I don't imagine this will affect your chances with HSBC.
N.B. As a general rule, you are more likely to be accepted for credit if you have debt that you manage properly rather than no debt at all! If you have no credit or do not use your credit facilities, you are deemed an unknown by lenders and as such are less attractive. Again, this may NOT apply to the agreement with HSBC.